Jewelry was a luxury item to the ancients and they did not have a bunch of knock-offs or cheap imitations available. From century to century, and kingdom to kingdom, gold was the most valuable commodity in their world. So the gold items mentioned in this verse were about as good as it gets!
The purpose of gold earrings or other jewelry has always been to make us look good and more attractive. This verse says our willingness to receive a wise man’s rebuke will have the same kind of effect on us – make us better and more attractive to people.
There was no money or banks in the Old Testament world. People generally had their wealth in a portable state, like jewelry. Any item made of gold would have been like money in the bank for them.
So the long lasting value and benefit of gold jewelry is an insightful comparison to the character developed by “a wise man’s rebuke to a listening ear” in this verse. If we are willing to hear it and receive it…it’s like money in the bank!